Vacuum-pump.



2 Sheets-Shept l.

Patented Jan. 22, 1901'.

c. E. LEGGETT. vAcuum PUMP.

1 Application filed June 25, 1900.;

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WITNESSES CHARLES LEGGETT, OF JOPLIN, MISSOURI.

VACUUM-PUMP.

SPECIFICATION formingpart of Letters Patent No. 666,536, dated January22, 1901. Application filed. June 25, 1900. serial No. 21,467. \NOmodel.)

To aZZ whom it may concern:

Be it known that I, CHARLES E. LEGGETT, a citizen of the United States,and a resident of Joplin, in the county of Jasper and State of Missouri,have invented a new and Improved Vacuum-Pump, of which the following isa full, clear, and exact description. I

This invention relates to a pump which is actuated by the pressure ofsteam against water to expel the same from the pump cylinder orreservoir, the steam being then condensed to form a vacuum or partialvacuum into which water flows to fill the cylinder.

The apparatus is constructed with special reference to its use in mineswhere it is necessary to have a pump capable of handling a great deal ofwater in a short time and also capable of being economically slowed downwhen the Water in the mine has been placed under control.

This specification is the disclosure of one form of the invention, whilethe claims define the actual scope thereof.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in both views.

Figure 1 is a vertical section of the invention, and Fig. 2 is a sideelevation thereof with parts broken away.

The pump is of the duplex sort and comprises two cylinder extensions 3,which communicate with an elbow 4, leading from the source of water. Thecylinder extensions 3 are respectively commanded by valves 5, which openupward or into the cylinder extensions to admit water therein, but whichserve to prevent. water flowing back into the elbow 4. The cylinderextensions 3 discharge into branches 6 of a pipe 7, which carries offthe water from the pump, and the branches 6 are respectively providedwith outwardlyopening valves 8, serving as check-valves to prevent thebackflow of water. The upper ends of the cylinder extensions 3communicate directly with cylinders 9, which serve also as condensers,the cylinders receiving the steam, which serves alternately to force thewater out of the cylinder extensions and upon the condensation of thesteam to create a partial vacuum, into which additional wa ter flows byatmospheric pressure, as is common in this class of apparatus.

In each cylinder 9 a preferably disk-shaped float 10 is arranged. Thesefloats are respectively carried loosely on stems 11. The down wardmovement of the floats on the stems 11 is limited by collars 10",fastened to the lower ends of the stems, whereby the stems are moveddownward when the floats drop. The stems pass up centrally through thecylinders 9 and out at the upper ends thereof, the stems 11beingconnected to clamps 12, which are fixedly secured thereto andpivotally mounted on the short arms of bell-crank levers 14, which arefulcrumed, respectively,

on the ends a cylindrical valve-casing 15,

mounted rigidly by legs 16 on the upper ends of the reservoirs 9. Theends of the cylindrical valve-casing 15 are closed, and communicatingwith the middle of this casing by a port 17 is asteam-supply pipe 18,having a valve 19 in command thereof. Carried on top of the valve-casing15 is a cylindrical auxiliary valve-casing 20, each end of which is openand in which work two piston-valves 21, such valves being spaced apartand fastened on a stem 22, which passes longitudinally through thesupplemental valve-casing 20 and has its ends respectively in connectionwith the bell-crank levers 14. A pipe 23 passes from the steam-supplypipe 18 at a point above the valve 19 and communicates with the interiorof the valve-casing 20 at the middle thereof. This pipe 23 is commandedby a cock 24. The auxiliary valve-casing 2O communicates with two ports25, which pass oppositely and respectively into comm unication with theend portions of the cylindrical valve-casing 15. The piston-valves 21are so disposed with respect to the ports 25 that when moved in oneposition, as Shown in Fig. 1, the right-hand port 25 will be placed incommunication with the steam-pipe 23, so that steam-pressure will beexercised in the right-hand end of the valve-casing 15, and when thevalves 21 are in the position opposite to that shown in Fig. 1 theleft-hand port 25 will be placed in communication with the steam-pipe23. When one port 25 is in communication with the steam-pipe 23, theother port is in communication with the atmosthat when the floats arenotunder the influ-- enoe of the water 9., when the pump is at rest) theheavier float will hang lower than.

the other, and thus the valves 21 will always be held at one of theextreme positions, so that one of the ports 25 is always incommunication with the steam-pipe 28, and the action of the pump may beinstantlystarted by simply opening the cook 24. This arrangement avoidsthe necessity of manually adjusting the floats before starting theoperation of the pump. It is immaterial which of the floats 10 is theheavier. In Fig. '1 I have shown the right-hand float as hollow, andconsidering that each float is made of some buoyant material ittherefore follows that the left'hand float is here supposed to be theheavier of the two.

Within the main or cylindrical valve-casing works a duplex piston-valve,comprising heads'26, held apart by a stem 27. Leading from thevalve-casing l5 and through the legs 16 and into the respectivereservoirs 9 are ports 28, which are located one at each side of theport 17 at the middle of the valve-casing 15, and which,with thevalve-heads 26, are so arranged that when the piston-valve of the casing15 is in the position shown in Fig. 1 the left-hand port 28 will be opentocommunication with the port 17 and the right-hand port 28 will beclosed. When the valve is in the opposite position, the communication ofthe ports 28 is reversed. Ears 29 are respectively formed on the innerfaces of the heads of the valve-casing 15, such-ears being engaged bythe piston-valve 26 to-prevent the valves from entirely closing theend'of the casing 15, thus leaving always a space in each end of thevalve-casing 15 into which steam may pass from the ports for the purposeof actuating the piston-valve 26. Expansive springs 26 are arranged tobear, respectively, against the piston-heads 26, so as to retard themovement thereof, all of which will be fully explained hereinafter.Baffle-plates are arranged in the upper ends of the reservoirs 9respectively opposite the ports 28 to diffuse the steam as it enters thereservoir. Tubes 31, passing from the water-pipe 7, extend,respectively, into the reservoirs 9 and are commanded by cocks 32.Check-valves 32 are also provided for the pipes 31, the

check-valves serving to prevent the steam from rushing from thecylinders into the pipe.

7. These tubes serve to conduct and'spray water into the reservoirs 9 toeffect the con-- the cooks l9 and 24 are open, the steam en teringbetween the valve-heads 26 by way of the port 17 passes via theleft-hand port 28 'dicated in Fig. 1.

eea ss into the left-hand cylinder 9, it :there acting upon the water inthe left-hand cylinder 9 and cylinder extension 3 and forcing the waterout of the same by way of the left-hand branch 6 of the pipe 7. Thesteam from the pipe 23' passes by way of the right-hand port 25 into theright-hand end of the casing 15 and there acts upon the valve 26 to holdit in the position shown. The right-hand port 28 having been closed bythe right-hand valvehead 26 and the steam in the right-hand cylinder 9havingbeen condensed,a partial vacu- "um is formed, which results in theopening of the right-hand valve 5 and in the inrush of water into theright-hand cylinder 9, as in- These operations go on (the right-handfloat 10 moving upon the stem 11 as the water rises in the right-handcylinder 9) until the water lowers in the lefthand cylinder sufflcientlyto cause the lefthand float 10 to drop-on itscollar 10 This throws thevalves 21 to the position opposite that shown in Fig. 1, causing theleft-hand port 25 to'communicate withthe pipe 23 and opening theright-hand port 25 to the atmosphere. When this takes place, thepistonvalve 26 is thrown to the position opposite to that shown in Fig.1,-thus closing the lefthand port 28 and opening the right-hand port 28.The water in the left-hand cylinder 9 and cylinder extension '3 will bythis time have been ejected therefrom,and when the steam is cut off fromthe left-hand cylinder 9 the steam remaining in the reservoiris'condensed, thus forming-a partial vacuum,-which results in drawing anew chargeof water into the left-hand cylinder. Simultaneously withthese operations the instant that the righthand port 28 isfplaced incommunication with the port 17 the steam rushes into the righthandreservoir 9 and acts on the water in the right-hand cylinder, forcingsaid water out, as has been explained. Inthis manner the pump operatesautomatically and continuously until the valves 19 and 24 are closed,thus stopping the operationof the-pump.

The steam in the cylinders is condensed by water passing through pipes31 from the pipe 7. During the operation of the pump the cooks 32 areopen and the steam entering the cylinders has at firstsufficientpressure to preponderate the water-pressure in the pipes 31, and thusthe water is kept out of the cylinders. WVhen the steam is cut off, itstill has preponderatiug pressure, thus keeping the water back andallowing the steam to act expansively in the cylinders. Finally, thesteam-pressure becomes so reduced that it is no longer greater than'thatof the water, and the water rushes into the cylinder to condensethesteam. At thisinstant the vacuum is formed, and the water rushes intothe cylinder through the valve 5.

In connection with this invention it is pointedout that during theoperation of the pump to regulate the output it is not necessary toadjust the valve. 19. The steam is al lowed to pass through the port 17in an unvarying volume. By regulating the valve 24 the amount of steampassing into the auxiliary valve-chamber 20 may be controlled, and sincethis steam actuates the valve 26 I am therefore able to control thespeed at which this valve operates, causing it to shift rapidly orslowly, according to the exigencies of the situation. It is furtherexplained that the valve-heads 26 being of the relative width shown willbring about the closure of both of the ports 28 every time that thevalve 26 is shifted. Reference to Fig. 1 will show that as the valve 26goes from the position illustrated in that view to the opposite positionthe heads of the valve respectively cover the ports 28 for a certainperiod of time, the duration of which depends upon the rapidity withwhich the valve 26 is shifted. The result of this arrangement is thatthe steam is cut off from both of the reservoirs once for each movementof the valve 26. Consequently ample time is allowed for the condensingof the steam and the formation of the consequent vacuum, so that thetendency is to keep the cylinders and reservoirs full of water ratherthan full of steam, and this insures keeping the reservoirs cool, andtherefore in condition properly and eifectively to condense the steam.In pumps of this class it has been frequently found to be a seriousdisadvantage that the condensation of the steam is not sure, resultingat times in drawing out the water from both cylinders and in filling thesame with steam, which cannot be condensed and which therefore stops theoperation of the pump until the reservoirs and cylinders can be cooled.The springs 26 also serve to retard the movement of the valve 26 fromone extreme position to the other, since the springs are of equalstrength and act to keep the valve in the neutral position, during whichboth ports 28 are closed. The time at which the valves 21 are actuatedmay be regulated by adjusting the stems 11 in the clamps 12. This matteris, however, not essential to my invention. e If desired, small pipes(not shown) may be passed into the cylinders and placed also incommunication with the atmosphere. These pipes should have check-valvesto prevent the escape of steam. By these means small volumes of air maybe admitted into the cylinders, which will lie on top of'the inrushingwater and prevent the latter from rising above the baffle-plates. Thenwhen the steam enters the cylinders, it being lighter than the air, theair will lie between the steam and the water and prevent direct contactbetween the two.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. A vacuum-pump having a cylinder or receiver, withan inlet and outlet port or ports for the liquid pumped, meanscommanding the steam-supply to the cylinder or receiver, and two floatsactuating said means for commanding the steam-supply, one of said floatsbeing heavier than the other for the purpose specified.

2. A vacuum-pump having a cylinder or receiver with an inlet and outletport or ports for the liquid pumped, means commanding the steam-supplyto the cylinder or receiver, a float located in the cylinder andconnected with the said means for commanding the steam-supply to actuatethe same, and a gravity device connected with said means for commandingthe steam-supply and Working in opposition to the float, the float andgravity device being of difierent Weights for the purpose specified.

3. A duplex vacuum-pump having two cyl inders or receivers each with aninlet and outlet port or ports for the liquid pumped, valve devices forcommanding the steam-supply to the cylinders or receivers, and a floatWorking in each cylinder and connected with the valve devices to actuatethe same, the floats being of different weights for the purposespecified.

4. A duplex vacuum-pump having two cylinders or receivers, each with aninlet and outlet port or ports for the liquid pumped, a valve-casingwith an intermediately-situated steam-inlet port and with steam-outletports at the sides thereof, the said outlet-ports leading to therespective cylinders, a reciprocal main valve working in thevalve-casing and comprising two separate heads connected by a stem theheads being disposed with the steam-outlet ports so that bothoutlet-ports are closed during certain periods of the operation of thepumps and means for actuating the valve.

5. A vacuum-pump having a cylinder or receiver with an inlet and outletport or ports for the liquid pumped, means conducting the steam to thecylinder, a main valve commanding the said steam-conducting means, asecond means conducting steam to the main valve for actuating the samesaid second steam-conducting means being separate from the firststeam-conducting means for the purpose specified, an auxiliary valvecommanding the second steam-conducting means, and a device for actuatingthe auxiliary valve.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

CHARLES E.'LEGGETT.

Witnesses:

GEo. W. LAYNE, R. T. I-IAsLETT.

